Limb manipulation in Knife Combat should be secondary to slash/counter slash and stick. A knife like this misses the point completely. Not to mention the fact using this knife as personal tool seems ridiculous.

1. Any edged weapon is better than none
2. If you're going to rely on edged weapons (any style/design), you need to train.
3. If you think knives are retarded; you should still train in their usage/defense.
4. If you're going to carry one...might as well carry 2-3.
5. If you're from the "School of #3", I really need to share some pics and real-life anecdotes of why you are the actual retard and that you need to give a lot of respect to any edged weapon.

That thing looks like a fishing tool "gone bad"---however; until you have seen whatever form/style of fighting that it was designed around (or its actual designed application), I'd withhold immediate judgment on it.

PS> If I saw you with something like that; I too would think that you were either

And... right. What does he think the thing is, a lightsaber? I don't think this thing has the mass or is anywhere near sharp enough to sever the bones of the wrist just by pivoting around it like that. Additionally, a more conventional fighting knife can be used to do everything he shows in this video with the exception of actually catching a wrist on the blade. Of course doing that requires those nice big telegraphed movements we all love so much.

My biggest problem with it is this: It looks like blade on blade contact to the outer edges would channel a blade directly into your hand. Other problems are the chisel grind and the fact that it must be horrible tip heavy due to its shape. The chisel grind issue is a bit of an antiquated one, I admit. It used to be that a chisel grind was the mark of a low-quality knife and that stigma has never left me, despite manufacturers like Emerson using chisel grinds. But whatever. I certainly won't be buying it.

If I was in the military and THAT GUY, I'd rather carry my bigass bowie knife strapped to my leg.

If I take a bowie, it'll stay in my assault pack. Biggest knife I carried on any deployment had a 6" blade and it was more than enough. Too big and you won't want to carry it. If you're stuck on a FOB, there's no real occasion to use it. Big knives are cool, and I like them a lot, but there's an upper limit of practicality in the real world.